The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Wilsonville you can determine when to plant bittercress by looking at the USDA zone info.

Planting Calendar for Bittercress

Frost tolerance for bittercress:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Bittercress do ok in moderate cold which tells us that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant bittercress in Wilsonville is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant bittercress and expect a good harvest is probably August. Any later than that and your bittercress may not have a chance to grow to maturity. Starting your bittercress indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Wilsonville the average date of last frost happens on March 15. You should expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Wilsonville is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Wilsonville it frosts late in the year after March 15 so make sure that you are ready to cover your bittercress if you have one of those late frosts.

USDA Zone Info for Wilsonville

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Wilsonville

You may be interested in your other planting guides for Wilsonville.